Methods are known for providing objects and compositions including food and pharmaceutical compositions with identification. See, for example, U.S. Pat. Nos. 4,189,996; 4,548,825; 5,006,362; 5,118,369; 5,376,771; 5,457,895; and 5,529,767. U.S. Pat. No. 6,481,753 to Van Boom et al. describes use of thermochromic inks to print variable confidential information for use in detection of copying or scanning. U.S. Pat. No. 6,692,030 to Phillips describes use of nanopatterns on a substrate for use in detecting copying. In many cases, however, prior methods have not been experimentally verified, or poorly demonstrated, and are generally inadequate for addressing present needs for identification. In particular, present identification needs have accelerated in view of heightened security concerns because of terrorism. Moreover, the economics of pharmaceutical development, especially, has resulted in expensive pharmaceuticals which can have price variation from country to country. This can encourage counterfeit and illegal trade activities. Also, governmental concern for health in view of drug counterfeiting is increasing.
Hence, a present need exists to provide objects and compositions, particularly pharmaceutical compositions, with microscale and nanoscale identification features which are difficult to detect, particularly with the naked eye or simple low resolution magnification methods such as a conventional magnifying glass. Technology is needed which can provide high throughput and is otherwise commercially attractive and in compliance with health regulations. A need also exists to develop technology wherein an identification feature can be put onto the object itself rather than a mere package for the object. In particular, the technology hurdles become great when feature sizes go from a micro scale regime into a nanoscale regime such as below one micron, and in particular, below 100 nm. In recent years, some advances in lithography have been reported but these advances have not been applied to the identification problems noted above.
In a preferred embodiment, the present invention also generally relates to nanolithography and etching, and more particularly, to systems capable of DIP PEN NANOLITHOGRAPHY™ printing (DPN™ printing) and deposition, coupled with etching and/or other methods for pattern transfer. DIP PEN NANOLITHOGRAPHY™ and DPN™ are trademarks for NanoInk, Inc., Chicago, Ill.). These methods unexpectedly can be advantageous and useful in the commercial context of counterfeit prevention.